Ernest hopkinson



.E. HOPKINSON. APPARATUS FOR MAKING PNEUMATIC TIRE CASINGS.

APPLICATION FILED- OCT. 25, 1919.

Patented Aug. 10, 1920.

2 SHEETS-SHEET 1- E. HOPKINSON.

APPARATUS FOR MAKING PNEUMATIC TIRE CASINGS.

APPLICATION FILED OCT. 25, 1919- 1,349,424, Patented Aug. 10, 1920.

2 SHEETSSHEET 2.

To all whom'z't may concern: I t y to I Be it known that I, ERNESTHorkrNsoN, a citizen of the United States, residing at omrso STATES oriice 1 ERNEST HOPKINSON, or NEW YORK, N. Y. i :fi

APPARATUS FOR MAKING PNEUMATIC-TIRE GASINGS.

New York city, county of New York, and State of New York, have inventedcertain new and useful Improvements in Apparatus for MakingPneumatic-Tire Casings, of-

which the following is a full,'clear,and exact description. 7 Thisinvention relates to an apparatus for making pneumatic tire casings,and. w more particularly to an apparatus for carrying out the methodsetforth in my prior, application Serial No. 303,136 filed JunefllO,

and when vulcanized under pressure in this condition on a core'dilferent port ons of the finishedtire are not equally capable ofwithstanding the strains encountered during use.

To avoid this the tires have been stretched and cured on air bags, or agaseous fluid or a liquid under pressure has been introduced directlyintothe' casing during vulcaniza-r tion. The air bags are expensiveandshort lived and if a' liquid or gaseous fluid be placed directly in atire casing itrequires a special metho'd'of manufacture to prevent thefluid from permeating the 'wall structure "of the tire and rendering thelatterfporous. In addition,'if the stretching operationis per-,

formed while using a liquid or gaseous filler in the casing the fiberstend to straighten out in a chordand become, inwardly dis placed fromtheir proper curved position in the tire body, sinp e the liquidorgaseous'.

filler 'oifer's no'appreciable resistance to-this displacement. By mymethodabove referred to a plastic under, pressure and .containing justenough liquid to'give itjthe desired fluidity is used to fill the tirecasing, and the latter then vulcanized while the plastic is maintainedunder a balanced pressure. This causes a' stretching and rearrangementof the fabric threads to properly tension them before vulcanization, thetire bodyris com pacted and there is no tendency of the plasmanneSpecification of Letters Patent. 4 Patented Aug 10, 1920. Applicationfiled October 25, 1919. sriai na assnae. i i

V ticflto permeate the tire/The plastic somewhat yielding, and thereforewhen outer rigid molds. are usedit does notsuba ject the fabric andbodyof the casing to the crushing. action exerted by a" rigid metal corewhen a casingis pressedbetween such 1 l a core and outer rigid moldwalls. ,At the same time due to the semi-solid nature ofthe plasticandthe pressureemployed the tire a is compacted and. stretched" as abovestated,

the sizeand shape of the old ca i are i accurately reproduced, and thesemi-solid filler offers enough resistance to prevent the tivelyto thetire body. I V I An object of the present invention is to provide asuitable apparatus for carrying out my abovementioned method.

in each tire during vulcanization. a a v A furtherjobject is. toprovide' an individual plastic reservoir for each mold, supabovementioned objectionable straightening d and inwarddi'splacement of the;fibers rela- I ported-by and movable as a unit with the mold, but at tthe same time readily remow g I able therefrom.

In the drawing a 5i.

Figure 1 isaside elevationfshowing the 1 d mainpplastic reservoirs for.filling the tire casing, and showing a mold partly in sec tionfhaving' atire casing therein connected to one of the reservoirs. j Fig. 2 is atop plan view of a tire mold with an indi' ported the'reinl" t I t vFig. 3, isabrokensectionl showing the on the'mold.

Referring tothe drawings the numeral :1

is applied to] a; support upon which is mounted a reservoir 2 for the 1plast c. A

i'dual plastic; reservoir; sup

v of supporting thefpla stic reservoir? number'of reservoirs 2*may beused, and

in the present instancethey are mou'ntedin 7 pairs. A compressed airsupply pipe 6 w th aivalv'e 7 therein is providedwithbranches leadingintothe upper portions of tlie jb tanks 2, valves 9 being disposed inthe T branches .8. q A flexible h se 10'is connected to," the bottoin ofeach tank, the ,free e'nd fof the hose beingprovided with a metal elbow,

11 provided With a valve 12 and coupling 13. Secured to the compressedair supply pipe 6 are brackets 14: upon which the hosesections;

1O may be supported by their valves 12 when not in use. The tire casingsmay if desired be filled with plastic before; being placed in the molds,but as the plastic is supplied under pressure it-is. necessary toconfine the edges of the casing against move- IIlGILt, and it istherefore preferable tov fill the c'asings'aiter theirwalls aresubstantiallyin I their normalposition andconfined against outwardmovement.

. tire casing when in position. In thepipe is a Valve 26 having a pipenipple 27 leading therefrom. Disposed within the inner periphery of theannular tire mold is a seg mental ring-shaped auxiliary plasticreservoir 28. Surrounding said'reservoir at intervals are brackets 29,extensions ofwhich are adapted to rest in the recesses 30 formed in themold sections 16. Leading from one end of the reservoir 28 is apipe-nipple 3-1 valve 34; lea-d's fromthe other end of the reshaving avalve 32 therein and a coupling 33 at its end. A clean-out and pressurerelief ervoir 28,. V

In operation, a; tire casing having beenplaced in the mold'as shown inFig. 1, the

coupling 13' of the'hose 10 is connected, to

' the nipple 27 and thelval'ves 12 and 26 opened,-Jandthecasing filledwith plastic 7 under controlled. pressurefrom the re'ser voir 2. Duringthe filling operation the air may be removed from the casing in anydesired manner as by exhausting it through the valve 23 in the bullring. The pressure of the plastic results incompacting; the tire jcasing against the mold walls, and where the casing is of smaller sizethan the cavity in the mold, as shown in dotted lines in Fig. 1', itfurther results in afstretchingjof the a casing to. itsfinal sizeandpressing it against 1 the moldfwallsgfthereby properlytensioning l thethreads of the fabric. The entire form ing operation may becompleted atthis time if desired, including the formation oi'the tread and any.surface configurations thereto close thevalve 26, disconnect the hose 10on; I prefer, however, after the stretching operation hasbeensubstantially completed,

therefromfand to connect the nipple 31 of the auxiliary plastic"reservoir28 to the nipple 27by the coupling-33 .1 This auxiliaryreservoir has been. previously partly filled In Fig. 1 a tire casingwith plastic under a predetermined pressure by forcing the plasticthereinto through the nipple 31 until the air in the reservoir has beencompressed to the required degree. The relative quantities of plasticand air in the reservoir maybe. adjusted by use'of the pressure reliefvalve 34 during the filling operation. Uponconnection of the auxiliaryreservoir with the nipple 27 the valves 32 and 26 are opened, thusplacing the plastic in the tire casing under a predetermined andbalanced pressure. The mold with its accompanying auxiliary plasticreservoir 28 is then placed in the vulcanizer, and any furtherstretching or reshaping ofthecasing during vulcanization requiring achange. in the pressure of the plastic or the quantity required to fillthe casing is taken care of by the auxiliary reservoir 28 with its aircushion. It is very desirable that the pressure 'in each tire casingbeing vulcanized be individually controlled in order that ,a leak orother d'efeet occurring in the means for producing pressure may notaffect the whole batch of tires in the vul'canizer and ruin them. Bymounting individual auxiliary reservoirs within each mold as indicatedin Fig; 2' this .result is obtained whilev at the same time filled withplastic under pressure 'and an. individual. source of plasticunderpredetermined pressure disposed adjacent to and adapted to beconnectedwith the casing during vulcanization. 7

2. In an apparatus for forming and vul canizing tire casings, means forclosing a tire casing adjacent its rim-engaging portions, a moldsurrounding the outer walls of the casing, means whereby the casing maybe filled with plastic under pressure, and an individual source ofplastic under pressure carried by the mold and adapted to be connectedwith the casing after it is filled and remain imcommunication therewithduring vulcanization;

In an apparatus for forming and vulcanizmg 1311'6 casings, means forclosing a tire casing adjacent 1ts rim-engaging portions, amold'surroundmg the casing, means whereby the; casmgmay be filled withplastic and an ndlvldual' auxiliary plastic reservoir and adapted to beplaced in communication with the casing during vulcanization, saidreservoir being "disposed .within the periphery of the mold andsupported thereon.

maintained under predetermined pressure 4. In an apparatus for formingand vulcanizing tire casings, an annular tire mold, recesses on theinner periphery thereof, a, segmental plastic reservoir. disposed within5 the inner periphery of the mold and having brackets adapted to rest insaid recesses, and meansfor placing said reservoir in communication withthe interiorof a tire in said I mold. i i i Signed at New York, countyof New York, 10 and State of New York, this 24th day'of October, 1919.

ERNEST HOPKINSON.

